Solar compatiability ?

Question

I have a line on a couple panels from a local guy and while I think they will work with the system I have I thought I would ask you guys just to make sure.

I have 2 of these 100 watt panels from windy nation along with this 30A PWM controller

We haven't discussed price yet put I think I can get a good deal on 2 of these 85 watt Kyocera panelsThe panels came off a relay station so they have been used, not sure how old or how long they were in service.

Am I right in that they will work fine with my system? What would you guys pay per panel for these?

Thanks Jim S.

golden_hvac · Answer

If all the panels are around the same output voltage, you will be fine.

WHat I did is hook up my pair of 45 watt panels and 75 watt panel to one #10 gauge wire going to the controller, and the new pair of 120 watt panels to another #10 wire going to the panels. This way if there is a slight difference in the voltage output, it all comes together at the controller. I have a SB 50 amp controller that is MPPT.

So if one is say 21.2 open circuit and the other is within 1/2 volt of that, you will be fine.

If one set of panels is say 21.2 volts, and the other is say 42.0 volts, then a separate controller on each voltage panels is required, but still both can be hooked up to the same batteries.

Fred.

bfl13 · Answer

The 30 amp controller you have will handle that 370w (four panels in parallel) and leave the necessary 20% margin for when getting more amps than rated at times.

130w does 8.2a so "expected amps" at STC is 370/130 x 8.2 = 23.3a

20% margin = 4.7a + 23.3a = 28a so that works.

No idea on pricing for the used panels.

jrnymn7 · Answer

$40 each, max.

time2roll · Answer

Good to go. I would offer 50 cents per watt for used.

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Solar compatiability ?

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